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The morphological and biochemical response of calli and seedlings of different
rice cultivars were compared under acid saline conditions. Calli of
both tolerant and sensitive varieties showed severe stress symptoms like
browning and necrosis, but the onset of stress symptoms was delayed in
Pokkali. Seedlings of Pokkali showed minimal stress symptoms in lower
salinities, and curling and senescence of older leaves in higher salinities
although plants revived on amelioration of stress. Seedlings of the other
varieties showed severe stress symptoms even at low salinities and plant
death at higher salinities. Salt stress induced accumulation of the putative
osmoprotectant proline in calli and seedlings of all varieties. Proline accumulation
was higher in sensitive varieties than in Pokkali. These results
indicate that proline accumulation is not directly correlated with salt
tolerance in rice.

This study was undertaken to isolate ligninase-producing white-rot fungi for use in the extraction of fibre from pineapple leaf agriwaste. Fifteen fungal strains were isolated from dead tree trunks and leaf litter. Ligninolytic enzymes (lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac)), were produced by solid-state fermentation (SSF) using pineapple leaves as the substrate. Of the isolated strains, the one showing maximum production of ligninolytic enzymes was identified to be Ganoderma lucidum by 18S ribotyping. Single parameter optimization and response surface methodology of different process variables were carried out for enzyme production. Incubation period, agitation, and Tween-80 were identified to be the most significant variables through Plackett-Burman design. These variables were further optimized by Box-Behnken design. The overall maximum yield of ligninolytic enzymes was achieved by experimental analysis under these optimal conditions. Quantitative lignin analysis of pineapple leaves by Klason lignin method showed significant degradation of lignin by Ganoderma lucidum under SSF

Random genetic changes generated during in vitro culture are not desirable for plant
micropropagation and genetic transformation. RAPD markers were used to detect the variation in leaf disc callus
cultures of Jatropha curcas, maintained in Murashige and Skoog (MS) medium with different auxin and
cytokinin combinations. In total 41 scorable bands were produced with 11 primers. Out of 41 bands, 37 were
polymorphic (91.12%). The average number of polymorphic bands was 3.36 per primer. The highest similarity
(0.82) with mother plant was seen in callus maintained on MS with hormonal combination Indole butyric
acid - 0.4mg/l+ N6-benzyladenine purine - 4.0 mg/l. The callus grown on MS with hormonal combinations
IBA- 0.4mg/l+ BAP- 2.0mg/l, IBA- 0.4mg/l+ BAP- 2.5mg/l and IBA- 0.6 mg/l+ BAP- 2.0 mg/l also showed
similarity with the mother plant. Callus maintained on MS with hormonal combination IBA- 0.2mg/l+ BAP- 2.0
mg/l was found to show least similarity (0.53) with mother plant

Phenol is an aromatic hydrocarbon which exists as a colorless or
white solid in its pure state. Over the past several decades, there is
growing concern about wide spread contamination of surface and
ground water by phenol, due to rapid development of chemical and
petrochemical industries. Phenol affects aquatic life even at relatively
low concentration (5-25mg/L). Treatment for removal of phenol
includes chemical as well as biological processes. Studies show that
ligninases such as Lignin Peroxidase and Laccase, produced by
Pleurotus sp., can degrade phenol. Spent substrate of Pleurotus
mushrooms consists of ligninases. Present work was to investigate the
potential of spent substrate of edible mushroom P. ostreatus for
biodegradation of phenol. P. ostreatus was cultivated on paddy straw.
After harvest, spent substrate was utilized for phenol degradation.
According to the enzyme profile of two ligninases present in the spent
substrate of P. ostreatus, maximum specific activity for Laccase was observed in 35 day old
spent substrate and LiP activity was maximum in 56 day old spent substrate, which together
contributed significantly for removal of phenol. Spent substrate of 35th and 56th day were
each incubated with phenol sample (1:1w/v) for one day, which resulted in degradation of
phenol by 48% and 45% respectively. From these results it appears that, spent substrate of P.
ostreatus can be used effectively to remove phenol from industrial effluents

Bioethanol is a liquid fuel obtained from fermentation of sugar/starch crops. Lignocellulosic
biomass being less expensive is considered a future alternative for the food crops. One of the main
challenges for the use of lignocellulosics is the development of an efficient pre-treatment process.
Pretreatments are classified into three - physical, chemical, and biological pretreatment. Chemical process
has not been proven suitable so far, due to high costs and production of undesired by-products.
Biologically, hydrolysis can be enhanced by microbial or enzymatic pretreatment. Studies show that the
edible mushrooms of Pleurotus sp. produce several extracellular enzymes which reduce the structural and
chemical complexity of fibre. In the present study, P. ostreatus and P. eous were cultivated on paddy straw.
Spent substrate left after mushroom cultivation was powdered and used for ethanol production.
Saccharomyces sp. was used for fermentation studies. Untreated paddy straw was used as control.
Production of ethanol from P. ostreatus substrate was 5.5 times more when compared to untreated paddy
straw, while the spent substrate of P. eous gave 5 times increase in ethanol yield. Assays showed the
presence of several extracellular enzymes in the spent substrate of both species, which together contributed
to the increase in ethanol yield

D.C. and a.c. electrical conductivities, dielectric constant and dielectric loss factor in single crystals of ethylenediammonium sulphate, (H3NCH2CH2NH3)(SO4), have been measured axiswise as a function of temperature. Anomalous variations in all the above properties at 480 K indicate the occurrence of a phase transition in the above material at this temperature. The existence of such a phase transition is also confirmed by DSC measurements. Electrical conductivity results are analysed and the activation energies of conduction at different temperature regions have been evaluated from the logσ vs 103T−1 plot. Possible mechanisms for the electrical conduction process are discussed, the available results being in favour of a proton transport model.

A simple experimental set-up is described to measure the electromagnetic shielding property of high Tc superconducting samples. Measurements were performed using HTSC materials in the form of laser ablated thin films, powders and sintered pellets. Samples used were Gd-123 in pure and doped form as well as a few Bi-based superconducting ceramics. For comparison, similar measurements were carried out on metals like aluminium, copper and μ metal. Very effective shielding was observed for HTSC materials compared to the conventional materials mentioned above. However it also depended on the sample types and poor shielding was observed for powdered HTSC material in comparison to thin films prepared by laser ablation.

The effect of the chemisorbed hydroxyl groups on the thermal diffusivity of gama alumina is determined
by evaluating the thermal diffusivity at various degassing temperatures and by doping it with rare
earth oxide using photoacoustic technique. The thermal diffusivity is found to decrease with the
increase in degassing temperature as well as with the increase in the doping concentration of rare
earth oxide. This decrease has been attributed to the loss of hydroxyl ion from the y-Al2O3.

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Excitation and emission spectra of SrS : Mn : Ce phosphors have been studied in detail
at various Mn and Ce concentrations. In order to study the effect of external pressure on phosphors,
the samples were pretreated under various pressures. Four bands around 470 nm, 530 nm,
310 nm and 620 nm were observed, when the samples were excited with 265 nm radiation. The
effect of pressure is to reduce the fluorescence ability of the phosphors, and the luminescence
vanishes above O· 1 ton m-2 pressure. The fluorescence ability, however, can be regained on retiring
the sample. The emission mechanism has been attributed to two luminescentcenters in the forbidden
gap. An appreciable amount of photocurrent has also been observed for the sample.